Papers by Keyword: Low-Temperature Plasma

Abstract: s The paper considers the development of an alternative method for obtaining functional materials based on tungsten carbide and its compounds using simple and sufficiently productive equipment. This method will allow using mineral dumps as a raw material base, in addition, it gives an opportunity to obtain new compounds based on tungsten. Obtained during plasma-chemical synthesis, the W_xCW alloy from a mixture based on a tungsten-containing concentrate has a two-phase composition consisting of carbides of the W_xCW group and metallic tungsten. According to preliminary calculations, the content of the carbide phase in the alloy is 88% and depends on the plasma synthesis processes, on the concentrate composition, and on the introduced carburetor volume. The synthesis was carried out using tungsten-containing concentrates by treatment of high-density energies (g> 10⁴ - 10⁵ W/cm²) in an inert gas medium. The stage of plasma-chemical synthesis of the W_xCW semi-finished product made it possible to obtain nanosized tungsten carbide crystals. This makes a possibility to synthesize a high-quality alloy with an ordered structure of the carbide phase during refinement and pressing. The carbide phase ordered structure contributed to an increase in the strength characteristics of the new refractory material.

Abstract: The work presents the study of technological considerations of the nanocomposite structure formation on complex profile surfaces under the influence of low-temperature plasma aimed at wear resistance increase of metal products, the research being conducted on the novel plant.

Abstract: The article shows ways to improve spectral analysis of materials accuracy. It is proposed to perform image processing of a low-temperature plasma cloud during the analysis of the quantitative composition of materials. The experiment and addition of technical equipment of the spectrometer with a video surveillance system are described. An algorithm data processing is given that obtained during by testing of standard samples in various regimes in which the quantitative composition of various materials is determined This paper describes the addition of radiation control sensors to modern spectrometer. The given conditions and standard samples used to obtain the main results.

Abstract: The atomic lines intensity of carbon and oxygen in low-temperature plasma are shown. Measurements are made at different distances from the electrode depending on the composition of the plasma forming gas mixture and external magnetic field presence.

Abstract: The paper reviews the results of investigations of the surface layer structure and properties of type 35-L steel and commercially pure titanium modified by plasma flows (arc plasma torch with the powder blown into an arc), electro-explosive alloying of titanium specimens, and high energy electron-beam treatment performed on the vacuum electron-beam plant SOLO. It is shown that the surface treatments under review have lead to a multilayer and multi-phase structure formed by crystalline particles of sub-microsized and nanosized range, mechanical (microhardness) and tribological (wear resistance) properties of which exceed manifold that of the substrate material.

Abstract: The study focused on novel surface modification technology: low temperature plasma, which is characterized by clean, high efficiency and energy-saving. Polylactic acid (PLA) non-woven materials were treated by this means under different treatment time. The SEM and FT-IR were used to observe the surface properties and internal structures of samples. Whether the wetting contact angle and the biodegradable property of materials were modified by low temperature plasma was discussed. The results indicated that with the increase of treatment time, the etching effect of plasma and some functional groups especial hydrophilic groups increased significantly. When they were only treated 3 minutes the wetting contact angle declined from 113.86° to 85.49°. Additionally, the hygroscopicity and biodegradability of materials were improved by low temperature plasma treatment.

Abstract: We carried on the surface treatments to the cotton fabric (singed and hadn't been singed) with the low temperature plasma device. We studied the desizing performances, compared the capillaries. The results showed that after the same plasma treatment, the intensity of the singed hydrophilic was similar to those that hadn't been singed yet. We also explained the influence on hydrophilic, the results provide a scientific basis for the using of the pretreatment plasma technique in the future.

Abstract: In this paper, temperature-sensitive PET fabrics were prepared by Ar-plasma-induced simultaneous grafting Ploy-N-isopropylacrylamide (PNIPAAm) onto PET fabric. Fourier transform infrared spectroscopy (FTIR) was used to identify the structure of the grafted fabric. Then the surface morphology of the grafted fabric was observed from scanning electron microscopy (SEM) and AFM. The results show that the PNIPAAm was grafted onto PET fabrics, respectively. The grafted PET fabrics are characterized by differential scanning calorimetric analysis (DSC). The DSC analysis results indicated that LCST value of the grafted fabric was around 32°C. And the water permeability of the grafted sample showed a sharp change around 32°C. It was proved that grafted fabric was sensitive to temperature.

Abstract: This paper discussed the influences of plasma processing time and power on wool fibers, the results showed that: after plasma treatment, the surface of the wool fibers occurred varying degrees of physical and chemical etching phenomenon, the wetting property was increased significantly, anti-shrinkage performance was improved. Breaking strength and elongation at fracture were increased; the beginning of dyeing properties and the balance rate were increased.

Abstract: The treatment of resist water and oil by low-temperature plasma technology for recycled polyethylene terephthalate(PET)fiber automotive interior carpet was studied.The best process conditions were optimized:low-temperature plasma processing power was 150W,vacuum was 30Pa, time was 10 min,perfluorooctylsulfonyl amide(C₈H₂F₁₇NO₂S)monomer concentration was 15%.With angle measurement instrument,scanning electron microscopy and infrared spectroscopy,the performance of PET interior carpet on the condition of optimum process was tested and analysed.The result showed:there was cross-linked esterification between C₈H₂F₁₇NO₂S monomer and PET molecules,some C-F groups with low surface energy appeared on the fiber surface.Namely, C₈H₂F₁₇NO₂S monomer was effectively grafted onto the surface of PET fiber.The PET interior carpet had a better effect on resisting water and oil.